1. Field
The following description relates to a display apparatus having improved outdoor visibility. The present disclosure relates to a display apparatus that is switchable between a reflection mode and a transmission mode, and more particularly, to a display apparatus that may be operated in a reflection mode in strong outdoor light or in a transmission mode in low outdoor light, by using a color filter capable of wavelength-selectively transmitting or reflecting light.
2. Description of the Related Art
With the recent development of communications technologies and display devices, various kinds of mobile terminals such as mobile phones, personal digital assistants (PDAs), and mini notebook computers have been widely distributed. The mobile terminals may be characteristically used without restriction in many places, such as in strong outdoor light when not directly under the sun.
However, when a mobile terminal is used in strong outdoor light, visibility of a display apparatus may be deteriorated. In order to prevent such deterioration, brightness of the display apparatus may be increased. Although the simplest way to increase the brightness is to increase the output power of the display apparatus, power consumption of the mobile terminal increases accordingly. Since the power consumption of the mobile terminal is desired to be small in consideration of mobility, the method is difficult to adopt.
Furthermore, it is difficult for a transmission type display apparatus such as a liquid crystal display (LCD) to simultaneously have superior outdoor visibility and minimum power consumption, due to a limit in a structure thereof. For example, a conventional pigment-based color filter generally used for a transmission type display apparatus transmits light of a particular wavelength band only and absorbs light of other wavelength bands. Accordingly, about 60%-70% of light is lost by the color filter. To manufacture a color filter having higher color purity, a thickness of a color filter is increased and thus light transmissivity of a color filter may be further lowered.
In the meantime, a reflection/transmission switchable display apparatus has been suggested, wherein the reflection/transmission switchable display apparatus operates as a reflection type display in outdoor light by turning a backlight off and utilizing outdoor light, and as a transmission type display in low outdoor light by turning the backlight on and using the backlight. The display apparatus capable of switching between a reflection mode and a transmission mode may minimize consumption of power and increase outdoor visibility. However, in the suggested reflection/transmission switchable display apparatus, an area for a reflection mode and an area for a transmission mode are separately provided in a single pixel. Thus, since one pixel is divided into two areas, resolution in each of the transmission mode and the reflection mode is lowered. Also, maximum brightness may not be obtained in both of the transmission mode and the reflection mode.